NASA’s IBEX Helps Paint Picture of the Magnetic System Beyond the Solar Wind

A model of the interstellar magnetic fields – which would otherwise be straight — warping around the outside of our heliosphere, based on data from NASA’s Interstellar Boundary Explorer. The red arrow shows the direction in which the solar system moves through the galaxy. Image Credit: NASA/IBEX/UNH

IBEX research shows influence of galactic magnetic field extends well beyond our solar system

Understanding the region of interstellar space through which the solar system travels is no easy task. Interstellar space begins beyond the heliosphere, the bubble of charged particles surrounding the sun that reaches far beyond the outer planets. Voyager 1 has crossed into this space, but it’s difficult to gain a complete global picture from measurements in only one direction.

Spacecraft data in the past five years from near Earth and cosmic ray observations have painted a better picture of the magnetic system that surrounds us, while at the same time raising new questions. Scientists are challenging our current understanding in a new study that combines observations of massively energetic cosmic ray particles streaming in from elsewhere in the Milky Way along with observations from NASA’s Interstellar Boundary Explorer, or IBEX.

The data sets show a magnetic field that is nearly perpendicular to the motion of our solar system through the galaxy. In addition to shedding light on our cosmic neighborhood, the results offer an explanation for a decades-old mystery on why we measure more incoming high-energy cosmic rays on one side of the sun than on the other. The research appears in the Feb. 13, 2014, issue of Science Express.

“It’s a fascinating time,” said Nathan Schwadron, of the University of New Hampshire in Durham and first author on the paper. “Fifty years ago, we were making the first measurements of the solar wind and understanding the nature of what was just beyond near-Earth space. Now, a whole new realm of science is opening up as we try to understand the physics all the way outside the heliosphere.”

The heliosphere is formed as the constant stream of particles from the sun’s solar wind flows outward in all directions until it slows down to balance the pressure from the interstellar wind. The only information gathered directly from the heart of this complex boundary region is from NASA’s Voyager mission. Voyager 1 entered the boundary region in 2004, passing beyond the termination shock where the solar wind abruptly slows down. Voyager 1 crossed into interstellar space in 2012.

IBEX, which orbits Earth, studies these regions from afar. The spacecraft detects energetic neutral atoms that form from interactions at the heliosphere’s boundaries – an area that holds fascinating clues to what lies beyond. These interactions are dominated by electromagnetic forces. The incoming particles from the galaxy are made up of negatively-charged electrons, positively-charged atoms called ions, neutral particles and dust. Charged particles are forced to travel along the magnetic field lines that snake throughout space. Sometimes, a charged particle collides with a neutral atom at the outskirts of the heliosphere and captures an electron from the neutral atom. After stealing the electron, the charged particle becomes electrically neutral and speeds off in a straight line. Some of these fast neutral particles stream into the inner solar system and reach IBEX’s detectors. Depending on the speed and direction of those neutral particles, scientists can determine information about the atoms and magnetic field lines involved in the original collision.

In 2009, IBEX scientists presented research showing an uneven distribution of neutral atoms. There was a ribbon along the heliospheric boundaries sending a preponderance of neutral atoms toward IBEX.

Researchers wondered if this shape might also relate to an unevenness seen in cosmic rays. On Earth, we measure more cosmic rays – particles that stream in from the rest of the galaxy at 99% the speed of light – coming in from near the tail side of the heliosphere than from the other side. Teasing out the source and paths of incoming cosmic rays isn’t easy as the rays gyrate around magnetic field lines both inside and outside our heliosphere before colliding with other particles in Earth’s atmosphere, giving a shower of secondary particles that, in turn, are what we detect. To complicate things further, the heliosphere is moving through the galaxy.

“At some level, it’s like trying to determine the wind direction when you’re riding a bike very quickly and the wind isn’t particularly strong,” said Eric Christian, the IBEX project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md., and a co-author on the paper. “There’s some effect from the wind, but it’s small and hard to measure.”

The magnetic fields in interstellar space proposed by IBEX predict that cosmic rays would come in as shown on the right – blue represents fewer rays. This looks similar to what is actually observed, shown on the left, thus supporting IBEX’s findings.

Image Credit:

NASA/IBEX/UNH

To see if the IBEX data related to the cosmic ray observations, Schwadron used IBEX data to build a computer model of what the interplanetary magnetic field would look like around the heliosphere. Without the heliosphere, the field lines would be straight and parallel.

“But the heliosphere is kind of like an egg sitting in the middle of all these magnetic field lines,” said Schwadron. “The field lines have to distort themselves around that.”

With this model in hand, he simulated how the heliosphere would affect the cosmic rays. He assumed that the rays came in to the heliosphere evenly from everywhere in space, but allowed them to be warped based on the local magnetic geometry. The simulations showed a non-uniform distribution of cosmic ray particles that jibed well with the unevenness seen in observations.

“The analysis of this important paper strongly correlates with the theoretical view of the heliosphere from the numerical model developed by our team, which uses IBEX observations to derive the interstellar magnetic field direction,” said Nick Pogorelov, a space scientist at the University of Alabama in Huntsville, who works with IBEX data. “It shows that the heliopause that separates solar and interstellar plasmas is very long, maybe 2 trillion miles in the downwind direction, and therefore may affect the transport of high-energy cosmic rays toward the solar system.”

Unfortunately, this doesn’t prove that the heliosphere and the interstellar magnetic field are exclusively responsible for the cosmic ray mystery. However, this research shows that the magnetic configuration of our neighborhood does offer a potential answer.

Moreover, the agreement between what’s seen in the cosmic ray data and by IBEX provides outside confirmation of IBEX’s results of what the magnetic fields outside our heliosphere look like. That’s an interesting piece of the puzzle, when compared with Voyager 1’s measurements, because the Voyager 1 data provide a different direction for the magnetic fields just outside our heliosphere.

This doesn’t mean that one set of data is wrong and one is right, says Schwadron. Voyager 1 is taking measurements directly, gathering data at a specific time and place; IBEX gathers information averaged over great distances, so, there is room for discrepancy. Indeed, that discrepancy can be used as a clue. Understand why there’s a difference between the two measurements and we gain additional information. More IBEX observations and more Voyager observations will keep coming in. As with all research, more data will help unravel the picture and soon we will learn even more about how we fit into the rest of the universe.

eyesonu….Is our sun’s magnetic field aligned with the interstellar magnetic field?
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“The data sets show a magnetic field that is nearly perpendicular to the motion of our solar system through the galaxy.”

This seems to me to indicate it is approximately at right angles,..the Solar system ecliptic is at approximately right angles (about 62 degrees) to Galactic disc?

“Could this magnetic field be the reason our solar planets lie in a plane?”

Could be. The solar wind doesn’t emit in all directions equally, rather there is a dense plane of it in which all the planets lie; seems too much to be a coincidence; and it makes more sense than the accretion theory of solar system formation.

Newton’s gravity model was formed at a time when we thought space was empty. Now we know it’s filled with these plasma currents. Seems more obvious with time and observations these electric currents are at the heart of celestial mechanics.

IBEX research shows influence of galactic magnetic field extends well beyond our solar system
Well I always thought the galactic magnetic field extends beyond our solar system :) and not the other way around or am I missing something?

Another interesting point is that they talk of magnetic fields but forget electric currents. There is not such “magnetic charge” discovered yet.

It is good to see data from Voyager being collected and analysed. That was a fantastic realisation, still delivering data after so many years! Wonder when and which will be the next nation in position to send next probe to interstellar space.

So we have :
1) massive glactic scale magnetic fields.
2) the solar system/sun is spewing out massive amounts of plasma – which is an electric conductor
3) the solar system is moving through the galactic magnetic field.

What happens when you move a conductor through a magnetic field ? I remember learning about this in high school ? What could it be I wonder ? hehe.

Cosmic rays are charged particles with eg from ~1 MeV to as high as 10^21 eV. Charge particles present in the heliosphere are classified in four main populations: (1) Galactic CRs which originated far outside the heliosphere, probably accelerated during supernova explosions. When arriving at Earth, these particles are composed of ~98% nuclei (mostly protons), fully stripped of all their electrons, and ~ 2% electrons and fewer positrons. (2) Solar energetic particles which originate mainly from solar flares, coronal mass ejections and shocks in the interplanetary medium. They occur sporadically, and may have energies up to several GeV, observed in the inner heliosphere usually only for several hours mainly during solar maximum activity. These
events are directly linked to what is called space weather. (3) The anomalous components which were originally interstellar neutral atoms that got singly ionized relatively close to the Sun. They are transported as so-called pick-up ions to the outer heliosphere where they get accelerated up to a ~100 MeV through various processes. (4) The Jovian electrons which dominate the low energy electron spectrum up to 30 MeV within the first 10 AU from the Sun.

Galactic Cosmic Rays (GCRs) are energetic charged particles originated far away from
the heliosphere. The high energy GCRs may reach the Earth atmosphere to produce
secondary elementary particles that can be measured by ground-based Neutron Monitors
(NMs) or other detectors. Although the lower energy GCRs (tens of MeV/nuc) are not
usually detected by the ground-based NMs, they can be measured in space by spacecraft
except during solar energetic particle (SEP) events produced by solar ﬂares or coronal
mass ejections. Unlike SEPs, GCRs form a nearly stable and isotropic background of
high-energy radiation. The intensity of GCRs is slowly modulated in an anti-correlation
[McDonald, 1998] with the solar activity level of 11-year cycle. It occurs because GCR
particles have to travel through the magnetized interplanetary medium. The interplane-
tary magnetic ﬁeld emanated from the Sun changes with the solar cycle, causing variations in the speed of particle transport processes such as diﬀusion, convection, adiabatic de-
celeration and drifts. Therefore, GCRs can provide important information about their
propagation and modulation mechanisms in the heliosphere [K´ota, 2013]. Once the level
of modulation is ﬁgured out, we can reconstruct the spectrum and composition of GCRs
in the interstellar space, which can further provide information about their origin and the
acceleration mechanism that produces them at the source.
The GCRs intensity measured at the Earth reached a record high level during the
last solar minimum between cycles 23 and 24, noted as solar minimum P23/24 from now
on.http://arxiv.org/pdf/1310.7076.pdf

And how does one generate a magnetic field? With a moving electric charge. They’re just never going to get it are they. **Hangs head in resignation**
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ggm says:
February 15, 2014 at 4:23 am

So we have :
1) massive glactic scale magnetic fields.
2) the solar system/sun is spewing out massive amounts of plasma – which is an electric conductor
3) the solar system is moving through the galactic magnetic field.

What happens when you move a conductor through a magnetic field ? I remember learning about this in high school ? What could it be I wonder ? hehe.
**********************************
Astro Physicists were brought up on a diet of gravity when they should have been brought up on electricity. Wrong brain food. :)

I considered the gravitational force between two bodies and the centrifugal force of one rotating around another with a fluid surface of the smaller. This is where the discussion seemed to move to even though Willis’ original post was the attraction of a non orbiting body to another.

The previous discussion has me concerned that I may not know sh*t from apple butter. I will not cook breakfast at home tomorrow but will instead eat @ a fast food restaurant w/ no apple butter.

Tom in Florida says:
February 15, 2014 at 8:10 am
Imagine going to the next closest star at a distance of 4.5 light years.
===========
At 1 g acceleration-deceleration, the time required to reach the closest star is 3.6 years.

The record level of GCR intensity during the last solar minimum naturally throw
us a question: what causes the unusual solar minimum?
——————————————–

That is a good question, but from the IBEX observations at the heliospheric boundarys, we can see that the boundary is also changing along with our “unusual solar minimum.”
Figure shows the ribbon 0.7 – 4.3 kev side by side 2008-2011. Too bad we don’t have? 2012 and 2013 too?
3 Years of IBEX–Hi Maps
The first two sets of maps released by the IBEX science team were from IBEX–Hi, and the team has now released three full years of data from late 2008 through 2011 in new sets of IBEX–Hi maps:

Next image depicts IBEX observations of the “heliotail” region, with its Interstellar magnetopressure “dent” or offset.

The Heliotail Revealed by the Interstellar Boundary Explorerhttp://m.iopscience.iop.org/0004-637X/771/2/77/refs
D. J. McComas et al. 2013
“”Recent combined observations from the first three years of Interstellar Boundary Explorer (IBEX) data allow us to examine the heliosphere’s downwind region—the heliotail—for the first time. In contrast to a preliminary identification of a narrow “offset heliotail” structure,
we find a broad slow solar wind plasma sheet crossing essentially the entire downwind side of the heliosphere at low to mid-latitudes, with fast wind tail regions to the north and south. The slow wind plasma sheet exhibits the steepest ENA spectra in the IBEX sky maps, appears as a two-lobed structure (lobes on the port and starboard sides),
and is twisted in the sense of (but at a smaller angle than) the external magnetic field.
The overall heliotail structure clearly demonstrates the intermediate nature of the heliosphere’s interstellar interaction, where both the external dynamic and magnetic pressures strongly affect the heliosphere.””
with magnetic compression
inset enlargement of heliotail

And ren, complimentary to your referenced CLUSTER article (on vortex thread) concerning the recent VELOCITY (among other things) observations of the CLUSTER satellites and the IMF clock influence on the polar regions..
you might like some IBEX results too, of IMF y ..

..””Figure 3 shows the cusp ENA emissions from several
of the IBEX orbits; where the ENA emission for each spin is
normalized to the convected solar wind number flux corresponding
to that specific time. In addition, within the
magnetopause from the Tsyganenko model the projected
(into the YGSM = 0 noon‐meridian plane) emission locations
are adjusted so as to maintain the relative location with
respect to the cusp and to the magnetopause. This adjustment
is analogous to that performed by Lavraud et al. [2005,
Figures 1b and 1c] in their statistical examination of cusp
region observations from the Cluster mission for different
times and dipole tilt angles. As in Figure 2, in the intervals of
ENA emission shown in Figure 3 the relative brightness of the
northern or southern cusp regions is closely associated with
the tilt of the magnetosphere; specifically, the cusp region
oriented toward the Sun is the one with the greatest ENA
emissions.””..

ferdberple says:
February 15, 2014 at 3:05 pm
“At 1 g constant acceleration-deceleration, it would take about a month to reach Voyager 1.”

How would one supply the energy to keep a constant 1 g acceleration? What would be the top speed attained, when would deceleration have to take place to stop at the destination?
(not a challenge, just want to know)

And ren, I think too, that changing solar winds, do have an effect on on the rotating plasmasphere/radiation belts particle populations, which along with solar wind velocitys and additional solar wind particles propagate in a downward coherent as well as sporadic manner and have an effect on the vortex, at differing heights depending on what the planetary motions or other (tides etc) is being driven upwards at the time..
But am wondering if the plasmasphere/radiation belts have changed their angle due to overall reduction in solar wind pressures through out the interplanetary space.

Tom in Florida says:
February 15, 2014 at 8:10 am
Imagine going to the next closest star at a distance of 4.5 light years.
===========
At 1 g acceleration-deceleration, the time required to reach the closest star is 3.6 years.”

————————————————————————————————————-

I know 3.6 years has to be incorrect as it takes light 4.5 years and as we know nothing can travel as fast as or faster than light so how is it possible to complete the trip in only 3.6 years?

According to this ren, (loosely speaking) corotation of the plasmasphere is faster during periods of lower solar activity values. Another mark of lower solar activity..

On the causes of plasmaspheric rotation variability: IMAGE EUV observationshttp://plasmasphere.aeronomie.be/pdf/Galvan_2010_JGR_2009JA014321.pdf
David A. Galvan1,4, Mark B. Moldwin1,5,
Bill R. Sandel2, Geoff Crowley3
29 JAN 2010
pg.1
..In general, lower rotation rates correspond to higher
auroral and geomagnetic activity. We also make the first direct observation of
plasmaspheric superrotation. The plasmaspheric rotation rate is found to be highly variable
on multiday timescales, but the typical state of the plasmasphere is subcorotation, with
inferred mean values ranging from 88% to 95% of corotation, depending on L shell. In
addition, a statistical analysis shows that rotation rates near dusk are generally lower than
those at dawn, suggesting that local time and magnetospheric convection contribute to the
variation in rotation rate as well. We conclude that the cause of variability in
plasmaspheric rotation rate is a combination of storm phase, local‐time‐dependent
convection, and westward ionospheric drift.
pg.2
..Our analysis quantifies the variability of
plasmaspheric rotation and includes the first known observation
of plasmaspheric superrotation. Although Rishbeth et
al. [1972] discussed superrotation of the Earth’s upper atmosphere,
the phenomenon has never been clearly observed in
the plasmasphere.

Carla I’m no scientist, but I have a synthetic mind. I’m trying to connect the facts of the available observations. Why is this important? Because I believe that the climate is very sensitive to the parameters of the sunand these might change for decades.
First of all, you can see the huge influence of the Sun on the stratosphere and its waving at different heights. This changes the temperature gradients. Regards.

The record level of GCR intensity during the last solar minimum naturally throw
us a question: what causes the unusual solar minimum?
—————————–

I don’t know, I’m just a spaceweather stamp collector..

But on the subject of solar cycle modulation of Galactic Cosmic Rays..
They think they have found that there is more than one source direction. That the cosmic rays in the heliosphere have arrived from two different galactic sources. And that one source, is being modulated by solar cycle as we know it. But, that the other source is of a higher eV and is not following a dipole type of modulation, as their strength and gyro radius are extremely large..
Ya know, sounds like GCR above a certain eV level wont be solar modulated.. but instead, could be
at the higher electron volt levels, the GCR become the solar modulators.. shhhhhhh

Or, that recently, the GCR electron volt levels, in our local galactic neighborhood, has changed. Coming in at the same time as the usual GCR are now more with higher electron volt levels??? And from the same direction just being their speed and gyro radius make it harder to determine from which direction that they are coming???

And wonders if the higher electron volt GCRs are related to that discovery recently that the interstellar wind has changed direction?
Eleven Spacecraft Show Interstellar Wind Changed Direction Over 40 Years
“The direction of the wind obtained from the most recent data does not agree with the direction obtained from the earlier measurements, suggesting that the wind itself has changed over time,” said Eric Christian, the IBEX mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “It’s an intriguing result, which relied on looking at a suite of data measured in a bunch of different ways.”http://www.nasa.gov/content/goddard/interstellar-wind-changed-direction-over-40-years/

The increase of solar activity and the decrease in temperature in the stratosphere above the Arctic Circle?
Carla what you write is very important, because if it reaches the long solar minimum, the atmosphere and life on Earth may get a powerful dose of GCR. The larger the a minimum, the probability increases.

Changes in position and arrival direction for the PUIs (pick up ion) Crescent and PUI Focusing cone, are showing us the changes in interstellar wind direction. Earth is influenced by these PUI regions as it orbits around the sun.

Decades-Long Changes of the Interstellar Wind Through Our Solar Systemhttp://www.sciencemag.org/content/341/6150/1080
P. C. Frisch1,*, M. Bzowski2, G. Livadiotis3, D. J. McComas3,4,
E. Moebius5, H.-R. Mueller6, W. R. Pryor7, N. A. Schwadron5,
J. M. Sokół2, J. V. Vallerga8, J. M. Ajello9
Wind of Change
The flow of interstellar gas and dust through the solar system was thought to be unvarying, but Frisch et al. (p. 1080) show that there has been a significant variation of the direction of the flow of interstellar helium through the solar system over the past 40 years. The data, collected by 10 different spacecraft over much of the space age, hint of changes rather than constancy in the solar system’s galactic environment.

Fig. 1.
Historical variations of the ecliptic longitude of the interstellar wind direction. PUI, pickup ions. Measurements of the interstellar wind longitude are plotted against the time span over which the data were acquired. The historical data (table S1) are based on observations of the He o 584 Å backscattered emission (black), in situ He o measurements (red), and pickup ion data showing the

focusing cone (gray-blue) and upwind crescent (light green).

All data are plotted with dots, except for the crescent data, which are plotted with squares. The black long-dashed line shows a statistically likely fit to a simple model in which the flow longitude increases linearly with time, calculated by considering the longitude uncertainties and window of time of the observations; the green shading shows the uncertainties on this fit (supplementary text S5). The purple short-dashed line shows a statistical fit to a model with linearly increasing flow longitudes, where only the longitude uncertainties are included; the two vertical purple short-dashed lines show the uncertainties at each end of the time interval under consideration (supplementary text S5). The black horizontal dash-dotted line shows the fit resulting from the statistically unlikely assumption that the flow longitude has been constant over time and uncertainties on that fit (vertical black dash-dotted line). For clarity, some of the STEREO and Prognoz 6 data points are plotted using small shifts in the year of observation. The temporal interval over which some data were acquired is smaller than the plotted symbols.

Frightening explosions on the Sun, while the active Sun protects us from the greater danger. You may find that the airplane flight over the Arctic Circle will be harmful to children and pregnant women.

Tom in Florida says:
February 15, 2014 at 8:10 am Voyager 1 is just over 19 billion km from the Sun about 17.5 light hours away
Voyager 2 is almost 16 billion km from the Sun about 14.5 light hours away

And I think these are one of the fastest of anything human made yet (not counting the inwards Helios probes):
Voyager 1 is escaping the solar system at a speed of about 3.6 AU per year, currently at 127.2 UAT or 19,029,681,535 KM or about 17 km/sec

Voyager 2 is escaping the solar system at a speed of about 3.3 AU per year currently at 104.7 UAT or 15,665,691,535 KM

I’m not so sure I like it when spaceweather writers start saying things like, “petered out,”.. wrt CME impacts or lack thereof.

http://www.spaceweather.com/
“”STORM WARNING, CANCELED:
A brief geomagnetic storm on Feb. 15th sparked by a CME impact has petered out, and the chances for auroras this weekend are subsiding. The CME appears to have been a merger of three minor clouds that, even together, could not cause a sustained disturbance in Earth’s magnetic field. The hoped-for Valentine’s display of auroras never materialized.”’
Solar wind
speed: 368.5 km/sec
density: 10.8 protons/cm3
Interplanetary Mag. Field
Btotal: 9.9 nT
Bz: 5.3 nT north

Huh, the IMF went north..this will change flow directions of particles by comparison of Bz south

Carla, please explain to me why you not interested in serious of meteorologists that the polar vortex is blocked us from Siberia from autumn! After all, in the eyes of is beating. It is the cause severe of winter in the USA from October (snowstorm in South Dakota). I show at a glance:
1 Now the polar vortex a height of 30 km.
2.Aktualny polar vortex height of 17 km.
3 Circulation at 850 hPa.
On the final graphic can be seen as a weak polar vortex “lets” the warm air above the polar circle.
1.http://oi60.tinypic.com/vmsjyw.jpg
2.http://oi60.tinypic.com/jsfrbl.jpg
3.http://oi60.tinypic.com/so4n7d.jpg

Important new directions of research.http://chapman.agu.org/solarminimum/files/2013/04/AGU-CC13SM-22.pdf
———–
Yes .. there are lots in that document.
Wow.. lower thermosphere this minimum has attracted a lot of attention too, I see.. amongst the many abstracts in the link..
Lower thermosphere, with a possibly faster rotation of the plasmasphere.. sounds like some strong vortex mechanisms..